منابع مشابه
Strong proximinality of closed convex sets
We show that in a Banach space X every closed convex subset is strongly proximinal if and only if the dual norm is strongly sub differentiable and for each norm one functional f in the dual space X∗, JX(f) the set of norm one elements in X where f attains its norm is compact. As a consequence, it is observed that if the dual norm is strongly sub differentiable then every closed convex subset of...
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ژورنال
عنوان ژورنال: Journal of Approximation Theory
سال: 2011
ISSN: 0021-9045
DOI: 10.1016/j.jat.2011.01.001